96 research outputs found

    Nanopartículas a base de polisacáridos: quitosano

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    Extraction, purification and characterization of water soluble galactomannans from Mimosa pudica seeds

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    Water soluble galactomannans from seed endosperm of Mimosa pudica L. was extracted and characterized (Fig. 1). Nuclear magnetic resonance spectroscopy and Gas Chromatography results revealed the presence of 4-linked mannose backbone with galactose side chains linked at the C6 position. Scanning Electron Micrographs showed smooth, elongated and irregular granular structure of galactomannan. Structural analysis by Attenuated total reflection infrared spectroscopy presented the Mannose to Galactose ratio while the X-ray diffraction studies showed the presences of A-type crystalline pattern of the galactomannan. Thermo Gravitimetric Analysis showed the three steps weight loss event and determined the thermal stability. The results showed that the extracted polysaccharides are typically amorphous, thermally stable and have desirable properties for industrial application

    Antimicrobial, cytotoxicity and preliminary phytochemical determination of commonly used medicinal plants to treat oral cavity, urinary tract and gut infections by inhabitants of Borabu sub-county, Nyamira County, Kenya

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    Aims: The study aimed at determining the antimicrobial activities and cytotoxicity properties of medicinal plants collected from southwestern Kenya. Methods and results: A total of 23 ethanol extracts of selected medicinal plants were bio-assayed against Gram-negative bacterial strains (Escherichia coli NU14, Helicobacter pylori ATCC 700824, and Porphyromonas gingivalis ATCC 33277). Cytotoxicity tests were also carried out on mammalian cell lines (AGS, KB, and TR146). Preliminary type of phytochemical compounds present in the extracts was determined by thin-layer chromatography. Cassia didymobotrya plant extract (1 mg/mL) had strong antimicrobial activity against P. gingivalis (average zone of inhibition of 21.70 ± 0.88 mm, MIC 0.13 ± 0.00 mg/mL and MBC 0.50 ± 0.00 mg/mL). E. coli was resistant to all the extracts bioassayed. Leonotis nepetifolia (15.80 ± 0.20 mm) and Clerodendrum myriacoides (14.20 ± 0.44 mm) showed only moderate activity against H. pylori. Cell cytotoxicity results indicated a dose-dependent response against KB, TR146 and AGS cell lines with C. didymobotrya having IC50 values of 47.64 and 704.00 µg/mL on KB and TR146 cell lines, respectively. L. nepetifolia and C. myriacoides did produce IC50 of 0.1883 mg/mL and 0.1061 mg/mL against the AGS cell line respectively. Conclusion, significance and impact of the study: Most of the extracts had no or weak activity against test isolates, but C. didymobotrya leaves extracts showed strong activity against P. gingivalis. C. didymobotrya can offer alternative medicare to P. gingivalis conditions

    Current state of insect proteins: extraction technologies, bioactive peptides and allergenicity of edible insect proteins.

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    This review aims to provide an updated overview of edible insect proteins and the bioactivity of insect-derived peptides. The essential amino acid content of edible insects is compared with well-known protein sources to demonstrate that edible insects have the potential to cover the protein quality requirements for different groups of the population. Then the current methodologies for insect protein extraction are summarized including a comparison of the protein extraction yield and the final protein content of the resulting products for each method. Furthermore, in order to improve our understanding of insect proteins, their functional properties (such as solubility, foaming capacity, emulsifying, gelation, water holding capacity and oil holding capacity) are discussed. Bioactive peptides can be released according to various enzymatic hydrolysis protocols. In this context, the bioactive properties of insect peptides (antihypertensive, antidiabetic, antioxidant and anti-inflammatory properties) have been discussed. However, the allergens present in insect proteins are still a major concern and an unsolved issue for insect-based product consumption; thus, an analysis of cross reactivity and the different methods available to reduce allergenicity are proposed. Diverse studies of insect protein hydrolysates/peptides have been ultimately promoting the utilization of insect proteins for future perspectives and the emerging processing technologies to enhance the wider utilization of insect proteins for different purposes

    Self-assembled high molecular weight inulin nanoparticles: Enzymatic synthesis, physicochemical and biological properties

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    Inulin has interesting physicochemical and functional properties, and therefore a wide range of applications in the food and medical industries. It has gained great traction due to its ability to form nanoparticles and its possible application as nanovehicle for drug delivery. In this work, we demonstrated that the enzymatically-synthesized high molecular weight (HMW) inulin forms stable spherical nanoparticles with an average diameter of 112 ± 5 nm. The self-assemblage of HMW inulin nanoparticles is carried out during enzymatic synthesis of the polymer, and become detectable after a certain critical aggregation concentration (CAC) is reached. Both, the CAC and nanoparticle size are influenced by the reaction temperature. These nanoparticles are not toxic for peripheral blood mononuclear cells, at concentrations below 200 μg/mL; no significant prebiotic potential was detected in cultures of 13 probiotic strains. This work contributes to a better understanding of the formation of HMW inulin nanoparticles and their biological properties

    Elaboration of a teaching program in development cooperation in the University of Alcalá

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    COOPUAH, a group of teachers and researchers of the University of Alcalá (UAH), who belong to different disciplines, consider that the training offered to students in Development Cooperation by their institution has some deficiencies. The group pursues the general objective of reflecting about and evaluating in particular how this field is included in the university curricula in order to propose a teaching program that could fill the that gap. The main results highlight that the current teaching offer is insufficient, it comes from the environmental and health sciences fields, and in organizational level, is concentrated in the 2nd semester. We therefore believe that we need a multidisciplinary work to expand this teaching offer, redistribute it both semesters, and to offer a program addressed to all students of the University of Alcalá and recognized officially by the institutio

    In Vitro and Sensory Evaluation of Capsaicin-Loaded Nanoformulations

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    Capsaicin has known health beneficial and therapeutic properties. It is also able to enhance the permeability of drugs across epithelial tissues. Unfortunately, due to its pungency the oral administration of capsaicin is limited. To this end, we assessed the effect of nanoencapsulation of capsaicin, under the hypothesis that this would reduce its pungency. Core-shell nanocapsules with an oily core and stabilized with phospholipids were used. This system was used with or without chitosan coating. In this work, we investigated the in vitro release behavior of capsaicin-loaded formulations in different physiological media (including simulated saliva fluid). We also evaluated the influence of encapsulation of capsaicin on the cell viability of buccal cells (TR146). To study the changes in pungency after encapsulation we carried out a sensory analysis with a trained panel of 24 students. The in vitro release study showed that the systems discharged capsaicin slowly in a monotonic manner and that the chitosan coating had an effect on the release profile. The cytotoxic response of TR146 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, was reduced following its encapsulation. The sensory study revealed that a chitosan coating results in a lower threshold of perception of the formulation. The nanoencapsulation of capsaicin resulted in attenuation of the sensation of pungency significantly. However, the presence of a chitosan shell around the nanoformulations did not mask the pungency, when compared with uncoated systems

    Sistema integral de saneamiento ecológico. Proyecto de investigación COOPUAH 2014-15

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    VII Congreso Universidad y Cooperación al Desarrollo. La Universidad y los Objetivos de Desarrollo Sostenible, 29/03/2017-31/03/2017, Universidad Autónoma Cantoblanco, EspañaPresentación del proyecto Sistema integral de saneamiento ecológico para situaciones de emergencia en zonas no excavables o inundables (Grupo de Investigación COOPUAH, Universidad de Alcalá, 2015-16), formulado bajo tres hipótesis: (1) según determinadas condiciones EcoSan es apropiado para implementarse en situaciones de emergencia, (2) la gestión del residuo puede ser comunitaria y (3) para que sea sostenible debe tratarse como un sistema integral.Presentation of the project Integral System of Ecological sanitation for emergency situations in hard or flooded soils (COOPUAH research group, University of Alcala, 2015-16), formulated under three hypotheses: (1) under certain conditions EcoSan can be used from the beginning of the emergency, (2) the management of the waste can be community and (3) to be sustainable it must be treated as an integral system.Convocatoria 2014 de las "Ayudas para la creación y consolidación de grupos de investigación de la Universidad de Alcalá

    Nanoencapsulated capsaicin changes migration behavior and morphology of madin darby canine kidney cell monolayers

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    We have developed a drug delivery nanosystem based on chitosan and capsaicin. Both substances have a wide range of biological activities. We investigated the nanosystem’s influence on migration and morphology of Madin Darby canine kidney (MDCK-C7) epithelial cells in comparison to the capsaicin-free nanoformulation, free capsaicin, and control cells. For minimally-invasive quantification of cell migration, we applied label-free digital holographic microscopy (DHM) and single-cell tracking. Moreover, quantitative DHM phase images were used as novel stain-free assay to quantify the temporal course of global cellular morphology changes in confluent cell layers. Cytoskeleton alterations and tight junction protein redistributions were complementary analyzed by fluorescence microscopy. Calcium influx measurements were conducted to characterize the influence of the nanoformulations and capsaicin on ion channel activities. We found that both, capsaicin-loaded and unloaded chitosan nanocapsules, and also free capsaicin, have a significant impact on directed cell migration and cellular motility. Increase of velocity and directionality of cell migration correlates with changes in the cell layer surface roughness, tight junction integrity and cytoskeleton alterations. Calcium influx into cells occurred only after nanoformulation treatment but not upon addition of free capsaicin. Our results pave the way for further studies on the biological significance of these findings and potential biomedical applications, e.g. as drug and gene carriers

    Chitosan encapsulation modulates the effect of capsaicin on the tight junctions of MDCK cells

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    Capsaicin has known pharmacological effects including the ability to reversibly open cellular tight junctions, among others. The aim of this study was to develop a strategy to enhance the paracellular transport of a substance with low permeability (FITC-dextran) across an epithelial cell monolayer via reversible opening of cellular tight junctions using a nanosystem comprised by capsaicin and of chitosan. We compared the biophysical properties of free capsaicin and capsaicin-loaded chitosan nanocapsules, including their cytotoxicity towards epithelial MDCK-C7 cells and their effect on the integrity of tight junctions, membrane permeability and cellular uptake. The cytotoxic response of MDCK-C7 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, is not observable following its encapsulation. The interaction between nanocapsules and the tight junctions of MDCK-C7 cells was investigated by impedance spectroscopy, digital holographic microscopy and structured illumination fluorescence microscopy. The nanocapsules modulated the interaction between capsaicin and tight junctions as shown by the different time profile of trans-epithelial electrical resistance and the enhanced permeability of monolayers incubated with FITC-dextran. Structured illumination fluorescence microscopy showed that the nanocapsules were internalized by MDCK-C7 cells. The capsaicin-loaded nanocapsules could be further developed as drug nanocarriers with enhanced epithelial permeability
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